JPH0828164B2 - Intermittent device - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to an interrupting device that periodically interrupts contacts.

[Background Art and Problems to be Solved by the Invention]

2. Description of the Related Art Conventionally, as a light bulb that blinks periodically, a blinking ball with a built-in contact connecting / disconnecting mechanism using a bimetal has been widely used. When the electric current flows through the filament of the electric bulb and the electric bulb is turned on, the bimetal heated by the filament opens the contact to turn off the electric bulb, and then the filament cools, and the bimetal is cooled accordingly. When it is also cooled, the bimetal closes the contacts, and the electric current is passed through the filament to turn on the light bulb.

 However, such a flashing ball of the related art has a low productivity because (a) adjustment of the bimetal is troublesome.

(B) Since the contacts are opened and closed with a bimetal, the opening and closing operations of the contacts are slow, so the arc is generated during opening and closing of the contacts, resulting in severe wear of the contacts and a very short operating life. Become).

(C) Since the contacts are opened and closed with a bimetal, it is not possible to speed up the contact-intermitting cycle (light bulb flashing cycle). Also, the period cannot be made variable.

(D) After the power is turned on, the light bulb remains lit until the bimetal is heated to some extent, and it takes time to start blinking repeatedly after the power is turned on.

There was a problem such as.

Therefore, the inventors of the present invention, as an interrupting device capable of solving such a conventional problem, in the Japanese Patent Application No. 61-265528, an interrupting device for interrupting contacts by utilizing the shape memory effect of a shape memory alloy. Proposed a device. However, in the embodiment disclosed in the above-mentioned application, the total current flowing through the load (bulb in this case) passes through the shape memory alloy, so that the current flowing through the load is directly restricted by the rated current of the shape memory alloy. (Or conversely, the rated current of the load directly limits the current flowing through the shape memory alloy).

[Object of the Invention]

The present invention has been made to solve the above-mentioned problems, and has good productivity, long operating life, little heat generation, and can be made to have a fast or variable contact connection / disconnection cycle,
Moreover, the intermittent operation of the contacts starts at the same time when the power is turned on, and the current flowing through the load is not directly restricted by the rated current of the shape memory alloy (in other words, the current flowing through the shape memory alloy is not directly restricted by the rated current of the load). ) It is intended to provide an intermittent device.

[Means for solving problems]

An intermittent device according to the present invention includes a fixed contact, a movable contact that is brought into contact with and separated from the fixed contact, a movable member that can move between a first position and a second position, and the movable member is the first member. When moving from the position toward the second position and passing through a predetermined first passage point intermediate between the first position and the second position, the movable contact is moved from the fixed contact. On the other hand, the movable member is moved toward the first position from the second position while moving away from the second position, and the predetermined second passage point intermediate between the second position and the first position. And the movable contact is brought into contact with the fixed contact, the linkage mechanism mechanically links the movable member and the movable contact, and urges the movable member toward the first position. The biasing means and the fixed contact and the movable contact are directly connected to each other. And inserted power and load,
When the movable member is in the first position, it is in a state of being deformed from the memorized shape, and when it is heated to generate a shape recovery force, the movable member is moved from the first position to the second position. It is mechanically linked to the movable member so as to move toward the main body, and is electrically connected to the main current path mainly through which the current flowing from the power source to the load when the movable contact comes into contact with the fixed contact. And a shape memory alloy connected in parallel with.

[Action]

In the present invention, when the movable member is in the first position and the movable contact is in contact with the fixed contact, a current mainly flows from the power supply to the load through the main current path, and is parallel to the main current path. Part of the current flows through the shape memory alloy. Then, the shape memory alloy is heated by Joule heat to generate a shape recovery force, so that the movable member is moved from the first position to the second position. When it passes, the movable contact separates from the fixed contact, and the energization of the shape memory alloy and eventually the heating is stopped.

Further, when the shape memory alloy is cooled to a certain temperature by stopping the energization heating as described above, the shape memory alloy loses its shape recovery force, and therefore the movable member is moved by the biasing force of the spring means. It is returned from the second position to the first position, and with this, the shape memory alloy undergoes deformation again. Then, at this time, when the movable member passes through the second passage point, the movable contact comes into contact with the fixed contact again, and the current again flows through the shape memory alloy.

After that, the above operation is repeated, and the movable contact is periodically contacted with and separated from the fixed contact.

In the present invention, since the shape memory alloy is connected in parallel to the main current path mainly through which the current flowing from the power source to the load passes, the rated current of the shape memory alloy does not directly limit the current flowing to the load (conversely speaking). For example, the current flowing through the shape memory alloy is not directly limited by the rated current of the load).

It should be noted that if the movable member moves from the first position to the second position, the movable contact is immediately separated from the fixed contact, and if the movable member moves in the opposite direction, the movable contact comes into contact with the fixed contact immediately. In that case, both contacts are immediately separated when the shape memory alloy is heated, and both contacts are immediately contacted when the shape memory alloy is cooled, so that the following inconvenience occurs. That is,
When a current flows through the shape memory alloy and the shape memory alloy is heated to generate a shape recovery force, and the movable member moves from the first position to the second position, the movable contact immediately separates from the fixed contact and forms a shape. The energization of the memory alloy is stopped, the shape memory alloy cools, and loses its shape recovery force, so that the movable member returns to the first position and immediately the movable contact comes into contact with the fixed contact again. Is electrically heated to move the movable member toward the second position, and immediately the movable contact is separated from the fixed contact to stop the energization of the shape memory alloy, which causes the movable member to move toward the first position again. The operation that the movable contact comes in contact with the fixed contact immediately after returning will be repeated repeatedly in an excessively short cycle, and in reality, the movable contact is not clearly interrupted with respect to the fixed contact.
The phenomenon that the output of this interrupting device becomes like noise occurs.

However, in the present invention, due to the linkage mechanism,
When the movable member is moved from the first position toward the second position and passes through a predetermined first passage point between the first position and the second position, the movable contact is moved from the fixed contact. On the other hand, when the movable member is moved away from the second position toward the first position while passing away, and passes through a predetermined second passage point between the second position and the first position, the movable member moves. The contact is adapted to contact the fixed contact, and for movement of the movable member from the first position to the second position and vice versa for movement of the movable member from the second position to the first position. Since the contacts are opened and closed with a delay, the inconvenience described above can be prevented.

〔Example〕

Hereinafter, the present invention will be described based on embodiments shown in the drawings.

1 to 3 show an embodiment of the present invention.
FIG. 2 and FIG. 2 mainly show the mechanical structure, and FIG. 3 mainly shows the electrical connection relationship.

In this embodiment, 1 is a conventionally known microswitch, and the microswitch 1 is constructed as follows. A normally closed terminal 3, a normally open terminal 4 and a common terminal 5 are fixed to the case 2 (see FIGS. 1 and 2).
The figure shows the microswitch 1 with the lid removed from the case 2). The normally closed terminal 3 is fixed to the normally closed fixed contact 6 which constitutes the fixed contact of the present invention, and the normally open terminal 4 is fixed to the normally open fixed contact 7. A push button-shaped movable member 9 is fitted in the case 1 so as to be movable in a linear direction (direction of arrow A), and the movable member 9 is at a first position (case 2 shown in FIG. 1). It can be moved between a position where it projects the most outside) and a second position shown in FIG. 2 (the position where it is pushed most deeply into the case 2).

One end of a turning lever 8 is rotatably supported by the common terminal 5. The other end of the rotating lever 8 faces the end of the movable member 9 on the inner side of the case 2. Further, in the vicinity of the end of the rotating lever 8 on the movable member 9 side,
One end of the movable spring 10 is attached. The other end of the movable spring 10 extends between the normally closed fixed contact 6 and the normally open fixed contact 7, and the fixed contacts 6 and 7 are provided on the front and back of the other end.
The movable contacts 11 that are respectively brought into contact with and separated from each other are fixed.

The movable spring 10 has a curved portion 10a extending from the vicinity of the movable contact 11 to the movable member 9 side in an arc, and the end of the curved portion 10a on the movable member 9 side is the other portion of the movable spring 10. And is abutted on the bent portion of the common terminal 5. The movable spring 10 moves the movable member 9 toward the outside of the case 2 via the tip of the turning lever 8 due to the elasticity of the bending portion 10a regardless of the position of the movable member 9.
That is, it is biased toward the first position (the position shown in FIG. 1). At the same time, in the movable spring 10, the elasticity of the bending portion 10a causes the movable member 9 to move to the first position (the position shown in FIG. 1).
When the movable member 9 is in the second position (position in FIG. 2), the movable contact 11 is urged toward the normally closed fixed contact 6 when the movable contact 11 is in the normally closed fixed contact. It is supposed to urge toward 7. As described above, in this embodiment, the movable spring 10, which is the urging means for urging the movable member 9 toward the first position (the position shown in FIG. 1), simultaneously
It also constitutes a part of a linkage mechanism that mechanically links the movable member 9 and the movable contact 11.

Reference numerals 12 and 13 denote alloy mounting terminals whose positional relationship is fixed to the case 2. Both ends of a wire-shaped shape memory alloy 14 made of a Ti-Ni alloy are fixed to these terminals 12 and 13. . The shape memory alloy 14 is in contact with the movable member 9 at the intermediate portion outside the case 2, and is slightly bent at this contact portion. Then, when the movable member 9 is at the first position (the position shown in FIG. 1), the shape memory alloy 14 is in a state of being extended from the memorized length and is brought into contact with the movable member 9 as described above. There is.

As shown in FIG. 3, one pole of a DC power supply 15 is connected to the common contact 5. An incandescent light bulb 16 is provided between the other pole of the DC power supply 15 and the normally open terminal 4, and an incandescent light bulb 17 (load in the present invention) is provided between the other pole and the alloy mounting terminal 12. Has been inserted.

The normally closed terminal 3 is connected to the alloy mounting terminal 13,
Between this alloy mounting terminal 13 and another alloy mounting terminal 12, a shape memory alloy 14 and a diode 18 are inserted in parallel with each other.

 Next, the operation of this embodiment will be described.

When the movable member 9 is at the first position as shown in FIG. 1, the movable contact 11 is in contact with the normally closed fixed contact 6. In this state, the power source 15-common terminal 5-movable spring 10-movable contact 11-normally closed fixed contact 6-normally closed terminal 3-alloy mounting terminal 13-diode 18-alloy mounting terminal 12-bulb 17
-Current flows through the path of the power supply 15 and the light bulb 17 lights up.

Further, at this time, a voltage drop occurs in the diode 18, and this is applied to both ends of the shape memory alloy 14, so that a relatively small current corresponding to the voltage drop is applied to the shape memory alloy.
Flowing to 14, the alloy 14 is heated by Joule heat. Then, the shape memory alloy 14 contracts due to the shape memory effect in an attempt to return to the stored length, and the movable member 9 is pushed into the case 2 (that is, downward in the drawing).

Then, the rotary lever 8 is rotated counterclockwise in the figure, and at the same time, the end of the movable spring 10 on the movable member 9 side is moved downward in the figure. Then, when the movable member 9 passes a predetermined first passage point on the way from the first position (position in FIG. 1) to the second position (position in FIG. 2), the movable spring 10
Since the curved portion 10a of this time biases the movable contact 11 toward the normally open fixed contact 7 side, the movable contact 11 is always closed.
The normally open fixed contact 7 is contacted apart from. This allows
This time, power supply 15-common terminal 5-moving spring 10-moving contact 11
-Normally open fixed contact 7-Normally open terminal 4-Light bulb 16-A current flows in the path of the power supply 15, and the light bulb 17 and shape memory alloy
No current will flow through 14. Therefore, while the light bulb 16 is turned on, the light bulb 17 is turned off and the shape memory alloy 14 is stopped from being heated.

The movable member 9 is pushed to the second position (the position shown in FIG. 2) due to the contraction of the shape memory alloy 14 after passing through the first passing point. If the alloy 14 loses its shape recovery force when it is cooled to a certain temperature by stopping the heating by energization, the movable member 9 is again projected outward by the biasing force of the bending portion 10a of the movable spring 10. Go. As a result, the rotating lever 8 is rotated clockwise in FIG. 2 and the end of the movable spring 10 on the movable member 9 side is moved upward in the drawing, so that the movable member 9 moves to the second position. When passing through a predetermined second passage point on the way from the position (position in FIG. 2) to the first position (position in FIG. 1), the bending portion 10a of the spring 10 again keeps the movable contact 11 stationary. As a result, the movable contact 11 is separated from the normally open fixed contact 7 and comes into contact with the normally closed fixed contact 6 again. As a result, the electric current again flows through the electric bulb 17 and the shape memory alloy 14, the electric bulb 17 is turned on, the electric current stops flowing through the electric bulb 16, and the electric bulb 16 is turned off.

After that, by repeating the same operation, the shape memory alloy 14 is periodically energized to periodically press the movable member 9 of the microswitch 1, and the movable contact 11 is fixed to the normally closed fixed contact 6 and the normally open fixed state. As a result of being alternately contacted with the contact 7, the light bulbs 16 and 17 blink alternately. In addition, from this example, the light bulb
Even if 16 is removed, the movable contact 11 is intermittently connected to the normally closed fixed contact 6, and the light bulb 17 is periodically flashed.

Here, if the movable member 9 moves from the first position (the position shown in FIG. 1) toward the second position (the position shown in FIG. 2), the movable contact 11 is immediately separated from the normally closed fixed contact 6 and the normal contact is normally released. Assuming that the movable contact 9 separates from the normally open fixed contact 7 and comes into contact with the normally closed fixed contact 6 as soon as the movable member 9 moves in the opposite direction, the shape memory alloy is contacted. As soon as 14 is heated, the movable contact 11 separates from the normally closed fixed contact 6 and comes into contact with the normally open fixed contact 7, and as soon as the shape memory alloy 14 cools, the movable contact 11 separates from the normally open fixed contact 7 and becomes normally open. Since it comes into contact with the closed fixed contact 6, the following inconvenience occurs. That is, when a current flows through the shape memory alloy 14 and the shape memory alloy 14 is heated to generate a shape recovery force and the movable member 9 moves from the first position to the second position, the movable contact 11 is immediately released. The energization of the shape memory alloy 14 is stopped away from the normally closed fixed contact 6, the shape memory alloy 14 cools, and loses the shape recovery force. Therefore, the movable member 9 returns to the first position and immediately the movable contact 11 Comes into contact with the normally closed fixed contact 6 again, the shape memory alloy 14 is electrically heated again, the movable member 9 moves toward the second position, and the movable contact 11 immediately separates from the normally closed fixed contact 6. The energization of the shape memory alloy 14 is stopped, whereby the movable member 9 returns to the first position and the movable contact 11 immediately contacts the normally closed fixed contact 6 repeatedly in an excessively short cycle. Therefore, the movable contact 11 is actually The closed fixed contact 6 and the normally open fixed contact 7 are not clearly connected and disconnected, and the output of the normally closed terminal 3 and the normally open terminal 4 becomes a noise-like phenomenon.

However, in the present invention, the movable member 9 is moved from the first position toward the second position, and passes through the predetermined first passage point intermediate between the first position and the second position. Then, the movable contact 11 separates from the normally closed fixed contact 6 and comes into contact with the normally open fixed contact 7, while the movable member 9 is moved from the second position to the first position to the second position. The movable contact 11 separates from the normally open fixed contact 7 and comes into contact with the normally closed fixed contact 6 when passing a predetermined second passage point between the position and the first position. Since the contact is interrupted with a delay with respect to the movement of the movable member 9 from the position to the second position and vice versa, the movement of the movable member 9 from the second position to the first position. The occurrence of such inconvenience can be prevented.

In the present embodiment, the movable member 9 is at the first position (see FIG.
2) to the second position (position in FIG. 2), the movable spring 10 rotates while the movable contact 11 is in contact with the normally closed fixed contact 6, while the movable member 9 moves to the first position. In the process of moving from the second position to the first position, the movable spring 10 rotates with the movable contact 11 in contact with the normally open fixed contact 7 (that is, the movable spring 10 is slightly displaced in the above two cases). Since the first passage point and the second passage point do not coincide with each other, the position is displaced.

In this device, since no bimetal is used and there is no part requiring troublesome adjustment, the productivity is very good.

In addition, since the function of the movable spring 10 can speed up the opening and closing of the contacts, it is possible to suppress the generation of arcs between the contacts and dramatically extend the operating life compared to the conventional blinking ball, Can be suppressed (the temperature when the shape memory alloy 14 is heated can be suppressed to, for example, 100 degrees or less).

Further, since the shape memory alloy 14 can repeat shape recovery and deformation at high speed, the contacts can be switched at high speed.

Further, the contact switching cycle of the switch 1 as described above is
Adjustable by changing the length of shape memory alloy 14,
Generally, if the length of the shape memory alloy 14 is lengthened, the period also becomes longer, and if the length of the shape memory alloy 14 is shortened, the period becomes shorter. Further, the contact switching cycle of the switch 1 can also be adjusted by changing the electric power applied to the shape memory alloy 14.

The contact switching operation is started at the same time when the power is turned on.

Further, the current flowing through the shape memory alloy 14 is determined by the magnitude of the voltage drop in the electric diode 18,
When the current flowing through the diode 18 is within a certain range, the magnitude of this voltage drop is almost constant regardless of the current value.
The current flowing through the shape memory alloy 14 can be determined independently of the voltage applied to it.

FIG. 4 shows another embodiment of the present invention when an AC power source is used. In this embodiment, an AC power supply 21 is used instead of the DC power supply 15 in the above-described embodiment, and a combination of diodes 22 and 23 that are arranged in parallel and in opposite directions is used instead of the diode 18. The other structure is the same as that of the above embodiment.

Also in this embodiment, the same effect as the above embodiment can be obtained.

FIG. 5 shows still another embodiment of the present invention when an AC power source is used. In this embodiment, a bridge circuit of four diodes 24, 25, 26, 27 is used instead of the diodes 22, 23 in the embodiment shown in FIG. The other structure is the same as that of the embodiment shown in FIG.

Also in this embodiment, the same effect as that of each of the above embodiments can be obtained.

FIG. 6 shows still another embodiment of the present invention when an AC power source is used. Also in this embodiment, the structure of the microswitch 1 itself, the switch 1 and the shape memory alloy 14 are used.
The mechanical relationship between and is the same as in each of the above embodiments.

However, the electrical connection relationship is different from that of each of the above-described embodiments as follows. One pole of an AC power supply 21 is connected to the common terminal 5. A capacitor 30 is provided between the other pole of the AC power supply 21 and the alloy mounting terminal 12, an incandescent lamp 16 is provided between the other pole and the normally open terminal 4, and the other pole and the alloy mounting terminal 13 are provided. Incandescent light bulbs 17 are inserted between and. The alloy mounting terminal 13 is a normally closed terminal 3
It is connected to the.

 Next, the operation of this embodiment will be described.

The movable member 9 is at the first position (the position where the movable member 9 is projected most outside the case 2), and the movable contact 11 is the normally closed fixed contact 6
Power source 21-common terminal 5-
Movable spring 10-Movable contact 11-Normally closed fixed contact 6-Normally closed terminal 3
-Alloy mounting terminal 13-Light bulb 17-Current flows through the path of the power supply 21 and the reverse path, and the light bulb 17 is lit.

Further, at this time, a relatively small current determined by the relationship between the impedance of the series connection between the capacitor 30 and the shape memory alloy 14 and the resistance value of the light bulb 17 causes the alloy mounting terminal 13-shape memory alloy.
14-Alloy mounting terminal 12-Because it passes through the path of the capacitor 30,
The shape memory alloy 14 is heated by Joule heat. Then, the shape memory alloy 14 shrinks in an attempt to return to the memorized length, and pushes the movable member 9 to the second position (the position where the movable member 9 is pushed deepest into the case 2).

As a result, the movable contact 11 separates from the normally closed fixed contact 6 and comes into contact with the normally open fixed contact 7, and this time, the power source 21-common terminal 5-movable spring 10-movable contact 11-normally open fixed contact 7-
A current starts to flow in the path of the normally open terminal 4-light bulb 16-power source 21 and the opposite path, and the current does not flow in the shape memory alloy 14. Therefore, while the light bulb 16 is turned on, the shape memory alloy 14 is stopped from being heated.

Further, when the shape memory alloy 14 is stopped from being heated and begins to cool in this way, the alloy 14 loses its shape recovery force, so that the urging force of the movable spring 10 causes the movable member 9 to move from the second position to the first position again. The movable contact 11 comes into contact with the normally closed fixed contact 6 again while being moved outward to the first position. As a result, a current flows through the shape memory alloy 14 again, the bulb 17 is turned on, a current stops flowing through the bulb 16, and the bulb 16 is turned off.

Hereinafter, by repeating the same operation, the shape memory alloy 14 is periodically energized in this embodiment as well, and the movable member 9 of the microswitch 1 is periodically pressed,
As a result of the movable contact 11 being alternately contacted with the normally closed fixed contact 6 and the normally open fixed contact 7, the light bulbs 16 and 17 blink alternately.

Further, as described above, the current flowing through the shape memory alloy 14 is determined by the relationship between the impedance of the series connection between the capacitor 30 and the shape memory alloy 14 and the resistance value of the light bulb 17, so that the capacity of the capacitor 30 is set appropriately in this embodiment. By selecting
The current flowing through the shape memory alloy 14 can be determined independently of the current flowing through the light bulb 17.

FIG. 7 shows still another embodiment of the present invention, which is substantially a combination of a plurality of circuits shown in FIG.

1a to 1d are microswitches having the same structure as the microswitch 1 in each of the embodiments, and 14a to 14d are shape memory alloys having the same structure as the shape memory alloy 14 in each of the embodiments. The mechanical relationship of the alloy is also the same as in each of the above embodiments. Further, 31a to 31d are diode bridge circuits having the same structure as the bridge circuit in the diodes 24 to 27 in the embodiment of FIG. 5, respectively.

The movable contacts 11 of the microswitches 1a and 1c are connected to one pole of an AC power source 21,
The movable contacts 11 of 1b and 1d are connected to the other pole of the AC power supply 21. The normally closed fixed contacts 6 of the microswitches 1a to 1d are connected to one ends of the shape memory alloys 14a to 14d and one ends of the diode bridge circuits 31a to 31d, respectively.

The other end of the shape memory alloy 14a and the other end of the diode bridge circuit 31a are connected to the “other pole” of the AC power supply 21 via a light bulb 32. The shape memory alloy 14b
And the other end of the diode bridge circuit 31b are connected to the normally open fixed contact 7 of the microswitch 1a via the light bulb 33. The other end of the shape memory alloy 14c and the other end of the diode bridge circuit 31c are connected to a normally open fixed contact 7 of the microswitch 1b via a light bulb 34. The other end of the shape memory alloy 14d and the other end of the diode bridge circuit 31d are connected to the normally open fixed contact 7 of the microswitch 1c via a light bulb 35.

In this embodiment, in the initial state, the movable contacts 11 of the switches 1a to 1d are connected to the normally closed fixed contacts 6 as shown in FIG. When the power supply 21 is turned on in this state, the power supply 21-the movable contact 11 of the switch 1a-the normally closed fixed contact 6-the diode bridge circuit 31a-the light bulb 32-
Electric current flows through the path of the power source 21 and vice versa, and the light bulb 32
Lights up first.

Further, at this time, a voltage drop occurs in the diode bridge circuit 31a, and this is applied to both ends of the shape memory alloy 14a, so that a current corresponding to the voltage drop flows in the shape memory alloy 14a in the same manner as described above, and the alloy 14a is It is heated by Joule heat and shrinks in an attempt to return to the memorized length,
The movable contact 11 of the switch 1a is brought into contact with the normally open fixed contact 7.

Therefore, this time, mainly the power source 21-moving contact 11 of the switch 1a-normally open fixed contact 7-light bulb 33-diode bridge circuit 31b-normally closed fixed contact 6 of the switch 1b-moving contact 1
1-A current starts to flow in the path of the power supply 21 and the opposite path, and the light bulb 33 is turned on while the light bulb 32 is turned off.

This also causes a voltage drop in the diode bridge circuit 31b, which is applied across the shape memory alloy 14b, causing a current corresponding to the voltage drop to flow into the shape memory alloy 14b, heating the alloy 14b and storing it. It contracts in an attempt to return to the length that it is operating and the movable contact 11 of the switch 1b is brought into contact with the normally open fixed contact 7.

Therefore, next, mainly, the power source 21-moving contact 11 of the switch 1b-normally open fixed contact 7-light bulb 34-diode bridge circuit 31c-normally closed fixed contact 6 of the switch 1c-moving contact 1
1-A current starts to flow in the path of the power supply 21 and the reverse path, and the light bulb 34 is turned on, while the light bulb 33 is turned off.

This also causes a voltage drop in the diode bridge circuit 31c, which is applied across the shape memory alloy 14c, causing a current corresponding to the voltage drop to flow into the shape memory alloy 14c, heating the alloy 14c and storing it. It contracts in an attempt to return to the length that it is operating, and the movable contact 11 of the switch 1c is brought into contact with the normally open fixed contact 7.

Therefore, next, mainly, the power source 21-moving contact 11 of the switch 1c-normally open fixed contact 7-light bulb 35-diode bridge circuit 31d-normally closed fixed contact 6 of the switch 1d-moving contact 1
1-A current starts to flow in the path of the power supply 21 and the reverse path, and the light bulb 35 is turned on while the light bulb 34 is turned off.

This also causes a voltage drop in the diode bridge circuit 31d, which is applied across the shape memory alloy 14d, so that a current corresponding to the voltage drop is applied to the shape memory alloy.
Flowing to 14d, the alloy 14d is heated and contracts in an attempt to return to a memorized length, bringing the movable contact 11 of the switch 1d into contact with the normally open fixed contact 7. Therefore, the light bulb 35 is turned on once and then turned off as described above.

On the other hand, the shape memory alloy 14a changes the movable contact 11 of the switch 1a from the normally closed fixed contact 6 to the normally open fixed contact 7 as described above.
If you switch to, it will not be energized and will cool, so
It loses its shape recovery force and allows the movable contact 11 of the switch 1a to contact the normally closed fixed contact 6 again. As a result, a current again flows through the shape memory alloy 14a and the light bulb 32, and the operation of sequentially lighting the light bulbs 32, 33, 34, 35 again starts as described above.

Therefore, in this embodiment, the operation of sequentially turning on the light bulbs 32, 33, 34, 35 is repeated in a wavy manner.

FIG. 8 shows still another embodiment of the present invention. In this embodiment, one end of the light bulb 32 is connected to the normally open fixed contact 7 of the switch 1d, not to one pole of the AC power supply 21.
The other structure is the same as that of the embodiment shown in FIG.

In the present embodiment, first, when the movable contact 11 of the switch 1a is forcibly separated from the normally closed fixed contact 6 and temporarily brought into contact with the normally open fixed contact 1c, the light bulb 33, the diode bridge circuit 31b and the shape memory alloy. Electric current flows through 14b, and the light bulb 33 lights up. Then, in the same manner as in the case of the embodiment of FIG. 7, current is sequentially applied to the combination of the light bulb 34, the diode bridge circuit 31c and the shape memory alloy 14c, and the combination of the light bulb 35, the diode bridge circuit 31d and the shape memory alloy 14d. Then, the light bulbs 34 and 35 are sequentially turned on.

When a current flows through the shape memory alloy 14d in this way, the alloy 14d is heated and tries to return to the memorized length, so that the movable contact 11 of the switch 1d contacts the normally open fixed contact 7. Let Then, at this time, switch 1a
Assuming that the movable contact 11 has already been returned to the normally closed fixed contact 6 side, this time the power source 21-the movable contact 11- of the switch 1a
Normally closed fixed contact 6-Diode bridge circuit 31a and shape memory alloy 14a-Light bulb 32-Switch 1d normally open fixed contact 7
-Movable contact 11-Current flows through the power supply 21 and the reverse path, and the light bulb 32 is turned on.

Next, similarly to the case of the embodiment shown in FIG. 7, a current flows through the light bulb 33, the light bulb 33 is turned on, and thereafter the light bulbs 32 to 35 are sequentially turned on in a ring system.

Although the switch, the shape memory alloy, and the electric bulb are provided in four stages in the embodiment shown in FIGS. 7 and 8, the number of stages of these combinations may be any number of two or more.

Further, in each of the above-mentioned examples, as a shape memory alloy
Although a Ti-Ni alloy is used, other types of shape memory alloys can be used in the present invention.

In each of the above-mentioned embodiments, a pin push button type micro switch is used.
As disclosed in 61-265528, it is also possible to use a rotary type microswitch in the present invention. Further, in the present invention, it is not always necessary to use the micro switch, and other kinds of switch mechanisms may be used.

Furthermore, in each of the above embodiments, the load is a light bulb, but the interrupting device according to the present invention can also load other types of elements or circuits.

〔The invention's effect〕

INDUSTRIAL APPLICABILITY As described above, the disconnecting device according to the present invention has good productivity, long operating life, little heat generation, and can make the contact connecting / disconnecting cycle faster or variable, and the contact connecting / disconnecting operation at the same time when the power is turned on. It is possible to obtain the excellent effect that the current flowing to the load is not directly restricted by the rated current of the shape memory alloy (conversely, the current flowing to the shape memory alloy is not directly restricted by the rated current of the load). Is.

[Brief description of drawings]

FIG. 1 is a front view showing the mechanical structure of an embodiment of an interrupting device according to the present invention (however, the mythro switch is shown with the lid removed), and FIG. 2 is the mechanical structure in other operating states. FIG. 3 is a front view showing the configuration, FIG. 3 is a circuit configuration diagram showing an electrical connection relationship of the embodiment, FIG. 4 is a circuit configuration diagram showing an electrical connection relationship of another embodiment of the present invention, and FIG. FIG. 6 is a circuit configuration diagram showing an electrical connection relationship of still another embodiment of the present invention, FIG. 6 is a circuit configuration diagram showing an electrical connection relationship of yet another embodiment of the present invention, and FIG. FIG. 8 is a circuit configuration diagram showing an electrical connection relationship of another embodiment, and FIG. 8 is a circuit configuration diagram showing an electrical connection relationship of still another embodiment of the present invention. 1,1a-1d …… Micro switch, 6 …… Normally closed fixed contact,
8 ... Rotating lever, 9 ... Movable member, 10 ... Movable spring,
11 …… Movable contact, 14,14a ～ 14d …… Shape memory alloy, 15,21
...... Power supply, 17,32 to 35 …… Incandescent light bulb, 18,22 to 27 …… Diode, 30 …… Capacitor, 31a to 31d …… Diode bridge circuit.

Claims (1)

[Claims] 1. A fixed contact, a movable contact brought into contact with and separated from the fixed contact, a movable member movable between a first position and a second position, and the movable member having the first position. Is moved from the first position to the second position and passes through a predetermined first passing point intermediate between the first position and the second position, the movable contact separates from the fixed contact. , The movable member is moved in the opposite direction from the second position toward the first position, and passes through a predetermined second passage point intermediate between the second position and the first position. Then, a linkage mechanism that mechanically links the movable member and the movable contact so that the movable contact comes into contact with the fixed contact, and a biasing force that biases the movable member toward the first position. Means, and is inserted in series with each other between the fixed contact and the movable contact. A power source and the load, when the movable member is in said first position whereas in the state of being deformed from memory shape and is heated to generate a shape recovery force,
The power source is mechanically linked to the movable member so as to move the movable member from the first position toward the second position, and when the movable contact contacts the fixed contact. And a shape memory alloy electrically connected in parallel to a main current path through which a current mainly flowing from the load to the load is connected.